Drive shaft housing for outboard motors



3mm 9 1943- E. c. KIEKHAEFER 2,442,728

DRIVE SHAFT HOUSING FOR OUTBOARD MOTORS Filed March 17, 1948 2 Sheets-Sheet 1 June 1, 3948. E. c. KIEKHAEFER DRIVE SHAFT HOUSING FOR OUTBOARD MOTORS Filed March 1'7, 1948 2 Sheets-Sheet 2 F395 f/man 4 MM Patented June 1, 1948 DRIVE SHAFT HOUS ENG FOR OUTBOARD TOBS Elmer C. Kiekhaefer, Cedarburz, Wis.

Application March 17, 1948, Serial No. 15,313

Claims.

This invention relates generally to outboard motors and particularly to the drive shaft housings therefor and is a continuation in part of copending application Serial Number 772,344, filed September 5, 1947.

Heretofore, in the normal operation of outboard motors operational difliculty and unpleasant boating conditions have arisen as a result of water spray created by the underwater movement of a part of the outboard motor. This spray may reach the ignition system and air intake of the motor with the possibility of consequent motor failure. Also the spray may wet the operator and the interior of the boat.

It is a primary object of the invention to remove this difficulty and unpleasantness from normal outboard motor operation.

A further object of the invention is the provision of a splash guard which is cast integrally with a drive shaft housing.

Another object is to simplify the construction and facilitate the casting of the lower gear case housing by extending the drive shaft housing 2 Fig. 4 is a transverse sectional view of the drive shaft housing taken on line 4-4 of Fig. 2. The outboard motor illustrated comprises an upper housing and engine I, a drive shaft housing 2 and a gear housing 3.

The upper housing which contains the engine is generally open at the bottom and the engine I is generally of the internal combustion engine type with a magneto for ignition and an air intake for carburation. The engine 8 is supported on the drive shaft housing 2 which has suitable bearings and mountings for attaching the outboard. motor to the boat.

The drive shaft housing or member 2 and the gear housing or member 3 preferably separate just beneath a horizontal anti-cavitation plate 4 which is cast integral with the housing 2. Plate 4 is disposed above the propeller and serves to prevent cavitation.

The lower end of housing 2 has a rearwardly downwardly to include a splash guard and the mediate portion of the drive shaft housing 2 anti-cavitation plate and exhaust opening.

Another object is to provide an outboard motor in which only two cast housings are employed for the drive mechanism, one extending downwardly from the engine to include the anti-cavitation plate to house the drive shaft and the other extending downwardly from the first to house the gears and propeller shaft.

Another object of the invention is to provide a splash guard cast integrally with a drive shaft housing in which the splash guard serves as a reinforcing member for the hollow housing.

Another object is to provide a splash guard of symmetrical contour.

A still further object is to provide a drive shaft housing consisting of a single piece casting in which an anti-cavitation plate and splash guard are cast integrally with the housing.

Other objects and advantages will appear hereinafter in a description of an embodiment of the invention illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a side elevational view of an outboard motor secured to a boat and shows a splash guard and anti-cavitation plate on the drive shaft housing.

Fig. 2 is a detail side elevational view of the drive shaft housing;

Fig. 3 is a detail front elevational view of the drive shaft housing; and

extending shoe portion 5 which serves to provide a rearwardly and downwardly opening exhaust discharge for the housing.

A splash guard 6 is interposed along the interabove the water line. This guard member 6 is cast integrally with and forms a part of the drive shaft housing. The guard 6 extends circumferentially of the housing 2 in the form of a platelike flange which may be of substantially the same width and thickness throughout its entirety.

At normal running speed the splash guard will be substantially parallel to the surface of the water and above the water level at all times.

In turning the boat, the position of the outboard motor is changed relative to the boat and to the normal flow of water passing under the boat to present in certain instances the side of the drive shaft housing to the impact of the water and cause a considerable splashing. In such instances particularly, the entire length of the splash guard serves to shield both the engine and boat from spray and water. In shielding the engine the splash guard effectively prevents water from entering the carburetor air intake and also from shorting any of the ignition parts of the engine.

In addition to acting as a splash guard, memher 6 serves to strengthen the drive shaft housing. Because of its presence, the wall thickness of the housing member may be made thinner with a consequent saving in weight of the entire member. The splash guard should be disposed at a height above the water line where it efficiently catches he upward spray and returns, it downwardly. The actual location may vary depending upon the size of the outboard motor and boat, and should not be so high as to become ineffective for the intended purpose.

By casting the anti-cavitation plate 4 and splash guard 6 integral with the drive shaft housing 2 a more effective streamlining of the underwater parts may be obtained and the casting of the lower gear housing is greatly facilitated.

By placing the parting line between the two housings below the anti-cavitation plate, the gasket or seal employedbetween the drive shaft housing and gear case is below the water level at all times and is not subject to deterioration from overheating by exhaust gases.

By extending the drive shaft housing 2 upwardly to the engine it is possible to reduce the number of parts and to support and house the drive mechanism by means of only two castings.

Various embodiments of the invention may be employed within the scope of the accompanying claims. I

I claim:

-1. In an outboard motor having an internal combustion engine with a carburetor and an ignition system and a substantially vertical drive shaft extending downwardly from the engine to a propeller drive housed beneath the water in operation, a hollow tubular casting enclosing a substantial portion of the drive shaft above the water lever and secured at its lower end to the propeller drive housing beneath the water level, and a splash guard having an unobstructed flat undersurface, said splash guard being cast integral with said tubular casting and disposed above the water level and at an angle to said tubular casting to deflect water downwardly and thereby prevent spray from interfering with the engine ignition and carburetion.

2. In an outboard motor having an internal combustion engine with an ignition system and a substantially vertical drive shaft extending downwardly from the engine to a propeller drive housed beneath the water in operation, a hollow tubular casting enclosing a substantial portion of the drive shaft and secured at its lower end to the propeller drive housing beneath the water level, and a circumferential flange of substantial width having an unobstructed flat undersurface, said flange being cast integral with said tubular casting and disposed between the upper and lower ends of said casting at a position above and adjacent the water lever to constitute a splash guard effectively preventing spray from reaching the engine and its ignition system.

3. In an outboard motor having a substantially vertical drive shaft extending downwardly from the engine to a propeller shaft in the water to drive the propeller, a housing for said shafts constructed of a plurality of members and of narrow stream-lined shape for said under-water members to reduce underwater resistance, and

a splash guard encircling said housing and disposed above and adjacent the water level with a substantially flat undersurface for deflecting water downwardly as the housing moves through the water, said housing above and below, where it meets said splash guard having substantially the same cross sectional area, and said housing below said splash guard extending sharply to the undersurface of the splash guard.

' 4. In an outboard motor having an internal combustion engine with an ignition system and a substantially vertical drive shaft extending downwardly from the engine to a propeller drive housed beneath the water in operation, a hollow tubular casting enclosing a substantial portion of the drive shaft and secured at its lower end to the propeller drive housing beneath the water level, and a circumferential flange of substantial width having an unobstructed flat undersurface, said flange being cast integral with said tubular casting between the upper and lower ends of said tubular casting and disposed above and adjacent the water line and at an angle to said tubular casting to deflect water downwardly and thereby prevent spray from interfering with the engine ignition and carburetion.

5. In an outboard motor having a substantially vertical drive shaft, a stream-lined hollow cast housing enclosing a substantial portion of the drive shaft above the water and receiving the exhaust gases of the engine for discharging the same underwater, and an encircling flange cast integral with and constituting a part of said housing and being positioned intermediate the water line and the top of said housing and adjacent the water line, said flange having an unobstructed flat undersurfaoe and being disposed at an angle to said housing to effect cooling of the same and to deflect water downwardly and there- 'by prevent spray from interfering with operation 01' the motor. v

ELMER C. KIEKHAEFER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,335,059 Kallenbach Mar. 30, 1920 2,209,301 Johnson July 23, 1940 FOREIGN PATENTS Number Country Date 296,226 Great Britain Aug. 30, 1928 329,764 Great Britain May 29, 1930 OTHER REFERENCES Johnson Motors Company, Waukegan, Illinois, Handy Chart for 1941, Models KD and SD.

Elto Outboard Motor Company, Milwaukee, Wisconsin, Catalogue of 1931, pages 9 and 22. 

